Treesearch

It is critically important to determine and understand relationships between endangered species populations and landscape and habitat features to effectively manage and conserve populations and the habitats they rely on. Several recent studies focused on the golden-cheeked warbler (Setophaga chrysoparia), an endangered songbird that breeds exclusively in central Texas, USA, have used a reproductive index to link pairing and breeding success to various factors of interest. However, no field test has evaluated the performance of a reproductive index at estimating productivity of golden-cheeke...

Extractives are low molecular weight compounds and regarded as nonstructural wood constituents. These compounds are present in trees and can be extracted by organic solvents. Extractives consist of several classes of compounds that diversify the biological function of the tree. Fats are an energy source for the wood cells whereas terpenoids, resin acids, and phenolic substances protect the wood against microbial damage or insects. In this investigation, extractives from five softwoods and four hardwoods were separated into nonpolar and polar components. The softwoods used were southern...

The Rocky Mountains and western U.S. forests are impacted by the infestation of mountain pine beetles (MPB). MPB outbreak is killing pine and spruce trees at an alarming rate. These trees present a fuel build-up in the forest, which can result in catastrophic wildland fires. MPB carry blue-stain fungi from the genus Ophiostoma and transmit infection by burrowing into trees to lay eggs. Once attacked by a pine beetle, the host tree produces resinous compounds around the burrow in an effort to kill the invading insect. Mortality rate of the trees is less than one year. Lodgepole pine acetone...

Commercially available arbuscular mycorrhizal (AM) products were applied at an operational rate to eastern redcedar (Juniperus virginiana L.) nursery beds and containers to evaluate seedling growth and colonization responses. A field study at the Augusta Forestry Center in Crimora, VA, and a companion container study were initiated in the fall of 2012. MycoApply® Endo products containing the same four species of AM fungi were applied as a liquid, granular, or seed treatment. The field application of AM products did not result in early root colonization by AM fungi. By November 2013,...

A taxonomic and nomenclatural Catalogue of the adelgids (Hemiptera: Adelgidae) is presented. Six family-group names are listed, five being synonyms of Adelgidae. Twenty-two genus-group names, of which nine are subjectively valid and in use, are presented with their type species, etymology, and grammatical gender. One hundred and six species-group names are listed, of which 70 are considered subjectively valid.

Wood failure percentage (WFP) is an important index for evaluating the bond strength of plywood. Currently, the method used for detecting WFP is visual inspection, which lacks efficiency. In order to improve it, image processing methods are applied to wood failure detection. The present study used thresholding and K-means clustering algorithms in wood failure detection, and four kinds of plywood were manufactured to analyze the influences of wood species and adhesive. Results show that the detection by K-means clustering method is more accurate than thresholding method; it could better...

Research is being conducted to evaluate potential preservatives to replace zinc naphthenate (ZnN) for use in dip-treatment of wooden packaging materials. In this study, laboratory tests evaluated the efficacy of preservatives in protecting Southern pine and yellow poplar against decay fungi and termites. Nine preservatives were evaluated at one or two concentrations, and in some cases with two dip times. The results of this study indicate that higher concentrations of most of the preservatives evaluated will provide protection similar to or greater than that of ZnN. Four of the formulations...

We combine experimental and modeling results from a headwater catchment at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, to explore the link between stream solute dynamics and water age. A theoretical framework based on water age dynamics, which represents a general basis for characterizing solute transport at the catchment scale, is here applied to conservative and weatheringderived solutes. Based on the available information about the hydrology of the site, an integrated transport model was developed and used to compute hydrochemical fluxes. The model was designed to...

We formulate five guidelines for introducing new genera, plus one recommendation how to publish the results of scientific research. We recommend that reviewers and editors adhere to these guidelines. We propose that the underlying research is solid, and that the results and the final solutions are properly discussed. The six criteria are: (1) all genera that are recognized should be monophyletic; (2) the coverage of the phylogenetic tree should be wide in number of species, geographic coverage, and type species of the genera under study; (3) the branching of the phylogenetic trees has to...